The present invention relates to an apparatus for shredding automobile tires and more particularly to providing a compact and inexpensive tire shredder capable of handling both oversize tires and tire or tire recap fragments.
Used tires present many difficulties for recycling despite the many uses that can be made of the basic materials in the tires. For most uses, whole tires are not acceptable and the tires must be reduced to particles, or powder, for use. Generally, the finer the particles into which the tire is cut the more possibilities there are for recycling. Tires are, of course, made to be highly durable, particularly with respect to resisting cutting, which has forced recyclers to use large, expensive, heavy duty machinery to reduce used tires to small particles.
Large, heavy duty machinery is expensive and is efficiently used by only those who have a large, steady supply of used tires. The primary source of used tires is automobiles, and, more particularly, the tire stores where drivers have their autos maintained. Many such stores are not large enough to make efficient use of the heavy duty machinery previously required to reduce tires to powder. Thus, many stores store used tires until collecting enough to ship to a centralized recycling facility.
Tires are bulky relative to weight, which makes the storage of used tires inside difficult because of the large space required. The outdoor storage of used tires, while done, fosters health risks from water collecting inside the tires and providing a breeding ground for mosquitos. Storing used tires poses fire dangers both by providing a fuel source and because they produce heavy smoke when burning. The same bulkiness which makes tires inefficient to store also makes them relatively expensive to ship. A truck fully loaded with tires travels at far below its weight capacity.
The recycling of tires would be eased if they could be reduced at the source, since converting the tires to particles aids not only recycling, but also reduces the space requirements for shipping and storing.
Some inventors have tried to deal with this problem by making tire shredding equipment transportable. For example, U.S. Pat. Nos. 5,375,775 to Keller, et al. 4,374,573 to Rouse et al., 4,180,004 to Johnson, and 3,913,850 to Daniel are all directed to transportable machines providing the fine reduction of tires for recycling. After use, both the machinery and the debris must be removed. The patents do not address the storage problem of small and medium sized shops.
Applicant, in his application for patent on a Tire Shredder, application Ser. No. 08/738,027 filed Oct. 25, 1996 now U.S. Pat. No. 5,782,417, which is not admitted to be prior art with respect to the invention by its mention in this background section, provides an apparatus for shredding automobile tires of conventional ranges in size. The tire shredder is mounted in a support frame. The frame supports two parallel, vertically spaced rails on which are mounted a wheeled carriage. A variable speed, bidirectional motor provides reciprocating movement of the wheeled carriage parallel to the floor with the travel of the carriage limited by opposed relays, which are thrown by movement of the carriage. The wheeled carriage supports a cutting assembly which includes a drive motor and a drive shaft set parallel to the travel of the carriage having a plurality of circular saws mounted thereon. Tires are fed to the circular saws by a conveyer system. Bottom and top conveyers are constructed from T-bars set across parallel chains for gripping and urging tires into the saws. The bottom conveyer carries the tires substantially parallel to the floor. The top conveyor, substantially identical to the first., is positioned directly above the first conveyer, slanting downwardly toward the bottom conveyor from the opening for the tires to the discharge point adjacent the saws. The downward slope serves to compress the tires as they move toward the saws. The conveyers are driven by a variable speed motor. Yet another conveyer belt may be provided on to which tires may be thrown and carried into the cooperating top and bottom conveyers which feed the saws. A compact tire shredder able to handle debris and large tires is still needed for some applications.